Diurnal and seasonal changes in photosynthesis and photosystem 2 photochemical efficiency in Prosopis juliflora leaves subjected to natural environmental stress

Title:

Diurnal and seasonal changes in photosynthesis and photosystem 2 photochemical efficiency in Prosopis juliflora leaves subjected to natural environmental stress

Creator:

Shirke, P. A. and Pathre, U. V.

Identifier:

https://cdk.lib.cas.cz/client/handle/uuid:5e95a7c1-e51d-441d-b825-333d856d5690
uuid:5e95a7c1-e51d-441d-b825-333d856d5690
issn:0300-3604
doi:10.1023/A:1025864513663

Subject:

chlorophyll fluorescence, diurnal courses, electron transport rate, irradiance, midday depression, non-photochemical quenching, photoinhibition, and photosystem 2 temperature

Type:

model:article and TEXT

Format:

bez média and svazek

Description:

The plants of Prosopis juliflora growing in northern India are exposed to large variations of temperature, vapour pressure deficits (VPD), and photosynthetic photon flux density (PPFD) throughout the year. Under these conditions P. juliflora had two short periods of leaf production, one after the winter season and second after summer, which resulted in two distinct even aged cohorts of leaves. In winter with cold nights (2-8 °C) and moderate temperatures during the day, the plants showed high rates of photosynthesis. In summer the midday temperatures often reached <45 °C and plants showed severe inhibition of photosynthesis. The leaves of second cohort appeared in July and showed typical midday depression of photosynthesis. An analysis of diurnal partitioning of the absorbed excitation energy into photochemistry showed that a smaller fraction of the energy was utilised for photochemistry and a greater fraction was dissipated thermally, further the photon utilisation for photochemistry and thermal dissipation is largely affected by the interaction of irradiance and temperature. The plants showed high photochemical efficiency of photosystem 2 (PS2) at predawn and very little photoinhibition in all seasons except in summer. The photoinhibition in summer was pronounced with very poor recovery during night. Since P. juliflora exhibited distinct pattern of senescence and production of new leaves after winter and summer stress period, it appeared that the ontogenic characteristic together with its ability for safe dissipation of excess radiant energy in P. juliflora contributes to its growth and survival. and P. A. Shirke, U. V. Pathre.

Language:

Multiple languages

Rights:

http://creativecommons.org/licenses/by-nc-sa/4.0/
policy:public

Coverage:

83-89

Source:

Photosynthetica | 2003 Volume:41 | Number:1

Harvested from:

CDK

Metadata only:

false